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Title: First principles screening of destabilized metal hydrides for high capacity H2 storage using scandium (presentation had varying title: Accelerating Development of Destabilized Metal Hydrides for Hydrogen Storage Using First Principles Calculations)

Abstract

Favorable thermodynamics are a prerequisite for practical H2 storage materials for vehicular applications. Destabilization of metal hydrides is a versatile route to finding materials that reversibly store large quantities of H2. First principles calculations have proven to be a useful tool for screening large numbers of potential destabilization reactions when tabulated thermodynamic data are unavailable. We have used first principles calculations to screen potential destabilization schemes that involve Sc-containing compounds. Our calculations use a two-stage strategy in which reactions are initially assessed based on their reaction enthalpy alone, followed by more detailed free energy calculations for promising reactions. Our calculations indicate that mixtures of ScH2 + 2LiBH4, which will release 8.9 wt.% H2 at completion and will have an equilibrium pressure of 1 bar at around 330 K, making this compound a promising target for experimental study. Along with thermodynamics, favorable kinetics are also of enormous importance for practical usage of these materials. Experiments would help identify possible kinetic barriers and modify them by developing suitable catalysts.

Authors:
; ; ;  [1]
  1. (Univ. of Pittsburgh, Pittsburgh, PA)--last author not shown on publication, only presentation
Publication Date:
Research Org.:
National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV
Sponsoring Org.:
USDOE - Office of Fossil Energy (FE)
OSTI Identifier:
910563
Report Number(s):
DOE/NETL-IR-2007-005
Journal ID: 0925-8388; TRN: US200724%%237
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Alloys and Compounds; Journal Volume: 446-447; Conference: International Symposium on Metal-Hydrogen Systems: Fundamentals and Applications (MH1006), Lahaina, Maui, Hawaii, Oct.1-6, 2006
Country of Publication:
United States
Language:
English
Subject:
08 HYDROGEN; FUNCTIONALS; HYDRIDES; HYDROGEN; HYDROGEN STORAGE; KINETICS; MIXTURES; SCREENS; STORAGE; THERMODYNAMICS; hydrogen; hydrogen storage; density functional theory; destabilization reaction; metal hydrides; hydrogen absorbing materials; thermodynamic properties; computer simulations

Citation Formats

Alapati, S., Johnson, J.K., Sholl, D.S., and Dai, B.. First principles screening of destabilized metal hydrides for high capacity H2 storage using scandium (presentation had varying title: Accelerating Development of Destabilized Metal Hydrides for Hydrogen Storage Using First Principles Calculations). United States: N. p., 2007. Web. doi:10.1016/j.jallcom.2006.10.166.
Alapati, S., Johnson, J.K., Sholl, D.S., & Dai, B.. First principles screening of destabilized metal hydrides for high capacity H2 storage using scandium (presentation had varying title: Accelerating Development of Destabilized Metal Hydrides for Hydrogen Storage Using First Principles Calculations). United States. doi:10.1016/j.jallcom.2006.10.166.
Alapati, S., Johnson, J.K., Sholl, D.S., and Dai, B.. 2007. "First principles screening of destabilized metal hydrides for high capacity H2 storage using scandium (presentation had varying title: Accelerating Development of Destabilized Metal Hydrides for Hydrogen Storage Using First Principles Calculations)". United States. doi:10.1016/j.jallcom.2006.10.166.
@article{osti_910563,
title = {First principles screening of destabilized metal hydrides for high capacity H2 storage using scandium (presentation had varying title: Accelerating Development of Destabilized Metal Hydrides for Hydrogen Storage Using First Principles Calculations)},
author = {Alapati, S. and Johnson, J.K. and Sholl, D.S. and Dai, B.},
abstractNote = {Favorable thermodynamics are a prerequisite for practical H2 storage materials for vehicular applications. Destabilization of metal hydrides is a versatile route to finding materials that reversibly store large quantities of H2. First principles calculations have proven to be a useful tool for screening large numbers of potential destabilization reactions when tabulated thermodynamic data are unavailable. We have used first principles calculations to screen potential destabilization schemes that involve Sc-containing compounds. Our calculations use a two-stage strategy in which reactions are initially assessed based on their reaction enthalpy alone, followed by more detailed free energy calculations for promising reactions. Our calculations indicate that mixtures of ScH2 + 2LiBH4, which will release 8.9 wt.% H2 at completion and will have an equilibrium pressure of 1 bar at around 330 K, making this compound a promising target for experimental study. Along with thermodynamics, favorable kinetics are also of enormous importance for practical usage of these materials. Experiments would help identify possible kinetic barriers and modify them by developing suitable catalysts.},
doi = {10.1016/j.jallcom.2006.10.166},
journal = {Journal of Alloys and Compounds},
number = ,
volume = 446-447,
place = {United States},
year = 2007,
month =
}
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